13 nm high-efficiency nickel-germanium soft x-ray zone plates
2011 (English)In: Journal of Vacuum Science & Technology B, ISSN 1071-1023, E-ISSN 1520-8567, Vol. 29, no 1, 011012- p.Article in journal (Refereed) Published
Zone plates are used as objectives for high-resolution x-ray microscopy. Both high resolution and high diffraction efficiency are crucial parameters for the performance of the lens. In this article, the authors demonstrate the fabrication of high-resolution soft x-ray zone plates with improved diffraction efficiency by combining a nanofabrication process for high resolution with a process for high diffraction efficiency. High-resolution Ni zone plates are fabricated by applying cold development of electron-beam-patterned ZEP 7000 in a trilayer-resist process combined with Ni-electroplating. High-diffraction-efficiency Ni-Ge zone plates are realized by fabricating the Ni zone plate on a Ge film and then using the finished zone plate as etch mask for anisotropic CHF3 reactive ion etching into the underlying Ge, resulting in a Ni-Ge zone plate with improved aspect ratio and zone plate efficiency. Ni-Ge zone plates with 13 nm outermost zone width composed of 35 nm Ni on top of 45 nm Ge were fabricated. For comparable Ni and Ni-Ge zone plates with an outermost zone width of 15 nm, the diffraction efficiency was measured to be 2.4% and 4.3%, respectively, i.e., an enhancement of a factor of 2.
Place, publisher, year, edition, pages
2011. Vol. 29, no 1, 011012- p.
Crucial parameters, Etch mask, Ge films, High efficiency, High resolution, Nanofabrication process, Resist process, Soft X-ray, Trilayers, X ray microscopy, Zone plates, Aspect ratio, Diffraction efficiency, Fabrication, Germanium, Optical instruments, Reactive ion etching, X ray diffraction, X rays
Other Engineering and Technologies
IdentifiersURN: urn:nbn:se:kth:diva-31321DOI: 10.1116/1.3520457ISI: 000286679400015ScopusID: 2-s2.0-79551627215OAI: oai:DiVA.org:kth-31321DiVA: diva2:404728
FunderSwedish Research CouncilKnut and Alice Wallenberg Foundation
QC 201103182011-03-182011-03-142011-11-14Bibliographically approved